Peptidyl arginine deiminase-4-deficient mice are protected against kidney and liver injury after renal ischemia and reperfusion

M Rabadi, M Kim, V D'Agati… - American Journal of …, 2016 - journals.physiology.org
M Rabadi, M Kim, V D'Agati, HT Lee
American Journal of Physiology-Renal Physiology, 2016journals.physiology.org
We previously demonstrated that renal peptidyl arginine deiminase-4 (PAD4) is induced
after renal ischemia and reperfusion (I/R) injury and exacerbates acute kidney injury (AKI) by
increasing the renal tubular inflammatory response. Here, we tested whether genetic
ablation of PAD4 attenuates renal injury and inflammation after I/R in mice. After renal I/R,
PAD4 wild-type mice develop severe AKI with large increases in plasma creatinine,
neutrophil infiltration, as well as significant renal tubular necrosis, apoptosis, and …
We previously demonstrated that renal peptidyl arginine deiminase-4 (PAD4) is induced after renal ischemia and reperfusion (I/R) injury and exacerbates acute kidney injury (AKI) by increasing the renal tubular inflammatory response. Here, we tested whether genetic ablation of PAD4 attenuates renal injury and inflammation after I/R in mice. After renal I/R, PAD4 wild-type mice develop severe AKI with large increases in plasma creatinine, neutrophil infiltration, as well as significant renal tubular necrosis, apoptosis, and proinflammatory cytokine generation. In contrast, PAD4-deficient mice are protected against ischemic AKI with reduced real tubular neutrophil infiltration, renal tubular necrosis, and apoptosis. In addition, hepatic injury and inflammation observed in PAD4 wild-type mice after renal I/R are significantly attenuated in PAD4-deficient mice. We also show that increased renal tubular PAD4 expression after renal I/R is associated with translocation of PAD4 from the nucleus to the cytosol. Consistent with PAD4 cytosolic translocation, we show increased renal tubular cytosolic peptidyl-citrullination after ischemic AKI. Mechanistically, recombinant PAD4 treatment increased nuclear translocation of NF-κB in cultured human as well as murine proximal tubule cells that is inhibited by a PAD4 inhibitor (2-chloroamidine). Taken together, our studies further support the hypothesis that renal tubular PAD4 plays a critical role in renal I/R injury by increasing the renal tubular inflammatory response and neutrophil infiltration after renal I/R perhaps by interacting with the proinflammatory transcription factor NF-κB in the cytosol and promoting its nuclear translocation.
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